Macbook Pro no display image

[kris-hm]

I have a macbook pro a1286, that i believe is mid 2009 or mid 2010, not sure because i bought it second hand with this problem. The guy i bought it from said it was a mid 2009 but i entered the serial number in online and a website told me it was a macbook pro a1286, mid 2010.
Anyway,
It works completely fine on an external monitor but when its not plugged into an external monitor there is no image. I thought maybe the screen was bad so i bought a new one and replaced it but it didnt help at all.
When i turn the computer on you can see the screen turn on sort of, it goes from gray to black, with no back light and no image at all, even with a flash light, and when i power it off you can see the black fade. Its hard to explain, i hope someone understands what im saying.
Anyone got any ideas?
I dont want to do anything drastic if its not necessary, such as a reflow or something.

 

[triplelucky]

Do you know any history of the problem from the seller?

Liquid spill ? Any other info?

 

[kris-hm]

No, according to him there wasn't any damage like that, but I don't think that matters because I don't know that he was the original owner anyway. The outside doesn't appear damaged badly and I've already examined the board and I don't see anything unusual or any corrosion or any signs that liquid has been inside it.
I was reading that there is some kind of problem with the graphics card? But I don't know the symptoms of that. I'm sure replacing the motherboard would resolve the issue but I don't want to spend 300 dollars or more on a board if I don't have to. Maybe the resolution on the built in monitor is wrong since it displays on an external monitor correctly? I haven't tried reinstalling the os, because it doesn't seem like it would be a software issue. If it was software I would think the external video out would also be affected?
Idk

 

[triplelucky]

You’ve probably already done all the SMC and NVRAM resets.

With no video or backlight on the replacement display, you might want to put the original one back in.

Then try the resets again.

SMC has to recognize the panel in order to turn it on.

Also you could check the cable ends and connector under magnification. The pins are easily damaged.

You probably already know to pull the battery connector first so no power whenever you don’t really need it.

 

[kris-hm]

yes, i have tried the resets and i had removed the battery. According the the guy i bought it from he had bought a replacement screen already. so perhaps he bought the wrong one if it needs to recognize it?
But i bought one for model number a1286 which is what it is, or so this website says. The cable for the lcd is damaged slightly, my next step was going to be to replace it and see if the issue is resolved. Its not damaged badly, just a little, a pin or 2 slightly bent, but thats enough to cause malfunction. I bent the pins back into place before hooking up the screen with a flat head screw driver.
Sometimes when i plug the screen cable into the board it refuses to turn on, almost like its shorting, but it only happens every now and again. I just think since the cable is already damaged that every once in a while when i plug the cable in a pin bends slightly and causes a short.

 

[triplelucky]

Well it would probably be a good idea to stop until you get the new cable.

Depending on which pins short and how, you normally don’t get too many chances to repeat the experiment.

If you let the smoke out of it your troubleshooting will get more complicated.

 

[kris-hm]

Yea, I haven't tried many times because I don't want to mess it up. Right now it will turn on. I'm ordering a new cable Monday. Il update after I get it. I have a weird feeling this cable isn't going to change my situation though.

 

[kris-hm]

Okay, i got my cable today, plugged it in, computer fired up, but still no visible image. I can still see the screen turn on and go black but no image at all. I tried using a flashlight to see if i could see anything but nothing. I havent tried my resets yet though. Im waiting for a thunderbolt to hdmi cable so i can see what the heck im trying to do.
On the chance that the resets do not work, what other suggestions do you have?
I do appreciate all the help.

 

[triplelucky]

What does the sleep indicator light do without the external display attached when you start up only using the built in display?

 

[kris-hm]

I dont know where the sleep indicator light is, but if its the one i think it is, it does nothing. The computer boots like it should or atleast it seems to minus the image on the screen.
When i turn it on, it makes the sound, and then shortly the keyboard lights up as though its loading up.
As far as i can tell the computer is not sleeping.
Also i tried the resets and they didnt work either, but the one where i hold down the shift, control, option and power buttons all at the same time while the power block is plugged in is supposed to make the indicator light on the power cable cycle, atleast thats what i read, but mine did not cycle, it stayed a solid green, and i held the buttons for atleast 15 seconds.
My mac has an internal battery, i had removed the battery at first and tried, and i replaced the battery and tried again, but the indicator light would not cycle as far as i can tell.
Other ideas?

 

[kris-hm]

just want to make an update, I'm actually on the macbook itself right now using my tv as an external display. it works in every way, except the built in screen. And since i replaced the lcd with a brand new one, that tosses out the idea of the screen being bad, or the backlight giving out, right?
I still have the same issue even with the replaced screen, so i put the old one back in.
The macbook is a core 2 duo, mid 2009, according to the about information on the macbook. I tried all the resets and nothing worked, including the one where you hold option+command+p+r
Does the screen have an inverter? probably a stupid question since most screens are led now and apple isn't one to lag behind in technology as far as i know.
But there is no backlight on the built in display at all with either screen i tried..
The only think i can think is the board is damaged somehow, but i wouldn't imagine it being liquid damage since its working so perfectly through the external display, a component burnt out perhaps?
Anyone have any idea what component it might be? Or where i can get a motherboard that isn't going to cost me 300 dollars? I just checked ebay and he cheapest one that was posted was 286, but id be happier paying in the price range of 100 if possible..

 

[Barney63]

There is a thread about repairing the logic board on some MBPs, take a read of that and post in there. Good luck.

Barney

 

[kris-hm]

Alright, thanks

 

[jamesdean86]

Hello, i have the exact same problem, how did you fix it?
thanks

 

[kris-hm]

I haven't, in order to repair it you need to be skilled in component level repair first. You need to replace both the led back light driver chip and the fuse for it. That is how to fix the existing board. You could also send the board off to a professional shop and they may do that. There is a shop that is based in newyork that does these repairs. You can ship your board to them and they will make the repair. Otherwise replace the motherboard with a working one. It sounds like the 2009 models had this issue a lot, so don't doubt that if you do manage to find a working motherboard that the same thing won't happen to it eventually.